Semiconductor devices are made on substrates, such as silicon substrates, glass plates, etc., for use in computers, monitors, and the like. These devices are made by a sequence of fabrication steps, such as thin film deposition, oxidation or nitridization, etching, polishing, and thermal and lithographic processing. Although multiple fabrication steps may be performed in a single processing station, substrates typically must be transported between processing stations for at least some of the fabrication steps.
Substrates generally are stored in cassettes or pods (hereinafter referred to collectively as “substrate carriers”) for transfer between processing stations and other locations. Although substrate carriers may be carried manually between processing stations, the transfer of substrate carriers is typically automated. For instance, automatic handling of a substrate carrier may be performed by a robot, which lifts the substrate carrier by means of an end effector.
To gain access to substrates stored within a substrate carrier, a door of the substrate carrier may be opened via a door opening mechanism, typically positioned at a load port of a processing tool. Door opening operations should be performed in a manner that is efficient and does not lead to contamination of substrates within the substrate carrier. Accordingly, a need exists for improved substrate carrier designs, as well as for improved methods and apparatus for using the same.